The present application relates to reactive material stacks, and more particularly to reactive material stacks with tunable ignition temperatures.
Reactive materials are a class of materials which can react to generate heat through a spontaneously exothermic reaction without producing gaseous products or generating a large pressure wave. Reactive materials are thus useful in a wide variety of applications requiring generation of intense, controlled amount of heat, including bonding, melting and microelectronics where the release of energy needed can be triggered by external ignition with, or without, a source of oxygen. For certain applications, it may be important that the energy stored in the reactive materials is not released until needed. For example and when employed as erasure elements to induce phase transformation of phase change materials of phase change memory (PCM) cells in an integrated circuit chip, the reactive materials need to be benign during the back end-of-line fabrication process (which typically requires annealing the chip at a temperature up to 400° C.) and normal chip operations, but can be ignited quickly when a triggering event occurs, e.g., when the chip is compromised (e.g., lost or stolen) and a possibility of a security breach could occur.